Basic Full-Frame DSLRs

Canon 5D Mark II vs. Nikon D700 vs. Sony A900

Three high-end digital SLR cameras with full-frame sensors are currently priced at about $3,000 or less -- each with its special claim to fame:

• The Nikon D700 (*Est. $2,700), despite its comparatively low resolution of 12.1 megapixels, is recommended in more reviews than the other two -- and it's the only one with built-in flash.

• The Sony Alpha A900 (*Est. $3,000) provides 24.6 megapixels of resolution -- comparable with that of one of the top two cameras, the Nikon D3X (*Est. $8,000), which costs nearly three times as much. The Sony is also the only high-end digital SLR that builds image stabilization into the camera body itself.

• The Canon 5D Mark II (*Est. $2,700, body only) combines 21.1-megapixel resolution with HD video capability -- which reviews consider far superior to that of the only other digital SLR camera that can take movies, the entry-level Nikon D90 (*Est. $1,000 body-only).

The Nikon D700 gets a lot of attention because it's the first Nikon full-frame digital SLR priced this low. Experts consider its 12.1-megapixel resolution plenty for all but truly huge prints. In the relatively new DXO sensor tests, the Nikon D700 takes third place -- bested only by the much more expensive Nikon D3X (*Est. $8,000) and D3 (*Est. $4,350, body only) models. Of course an excellent sensor is only one factor in image quality, but reviews also praise the Nikon D700's autofocus, exposure metering and in-camera processing. Exposure metering takes color into account, and 51 autofocus points are another advantage.

The Nikon D700 produces images with very low noise even at the high ISO levels needed for low-light photography. Ken Rockwell's comparison of the Nikon D700 with the more expensive D3 (*Est. $4,350, body only) at ISO 3200 shows no discernable differences. Both cameras use the same sensor and processing, so this is not surprising -- but makes the D700 quite a good value. (The Nikon D700 can actually shoot at as high as 25,600 ISO.) The huge 100 percent viewfinder is another plus, as is the built-in flash. The Nikon D700 is also the only one of these three to use Nikon digital SLR lenses well -- automatically cropping images to fit these smaller lenses, which can't take full advantage of the D700's full-frame sensor.

As noted earlier, the Sony A900 is a good "budget high-end SLR camera" -- if such a phrase makes any sense at all. This is mainly because image stabilization is built into the camera body itself -- so you don't have to buy expensive image-stabilized lenses to get this feature. Minolta SLR lenses are no longer in production, but the secondhand market for them is very good. You can also use third-party lenses with the Sony.

We found quite a few reviews that conclude that the Sony A900 is an excellent buy for anyone with a collection of Minolta lenses. This is pretty much "damning with faint praise." The main criticism of the Sony A900 is its noise at high ISO levels. For most reviewers, the 24.6-megapixel resolution isn't a big enough advantage to overcome this drawback, and so only recommend this camera to those who already own compatible lenses. If you plan to shoot in dim light, noise-free images are critical.

The Canon 5D Mark II gives the Nikon D700 a closer run for the money, and it's a top pick in nearly as many reviews. The Nikon provides built-in flash, can use digital SLR lenses and is a bit better for action shots -- with 5 frames per second (fps) compared with 3.9 fps on the Canon. The Canon 5D Mark II has higher 21.1-megapixel resolution, though -- a significant advantage -- and an even better viewfinder. Perhaps most significant, comparison tests at Popular Photography rate the Canon images sharper at all ISO levels. (You can actually boost ISO to 25,600.) The main drawback is that some high-contrast images show a scattering of black dots.

Reviewers consider this "black dot phenomenon" a minor, temporary problem that Canon will be able to fix. If that's true, this makes the movie mode the real make-it-or-break-it feature. If the Canon 5D Mark II were really inferior to the Nikon D700 for still shots, the video capability wouldn't matter so much. But with equal or better image quality at all lighting levels, the Canon's HD movie mode does give it a huge advantage. Popular Photography concludes that the 30 fps video capability is "truly pro-caliber image quality." A monaural microphone is built in, but you can attach a stereo microphone.

The main advantage the Canon 5D Mark II's video capability has over taking movies with a smaller digital camera or an HD camcorder is its flexibility. The large sensor combined with various SLR lenses gives more aesthetic possibilities to the movie maker. You can put the subject in sharp focus but blur the background, or use a fisheye lens for special effects -- choices not possible with a camcorder.

Reviews say that even though SLR video capability will no doubt continue to evolve with future camera bodies, it's a viable feature on the Canon 5D Mark II. Unless you're already committed to Nikon or Minolta lenses, this is the natural pick for this price range and is thus included in our Best Reviewed section.

Note that although the earlier 12.8-megapixel Canon 5D (*Est. $2,000) is no longer in production, there are still new Canon 5D camera bodies for sale at retailers -- as well as used models priced even lower. If you want a full-frame sensor at a budget price, this is an option worth considering. The 2.5-inch LCD screen lacks the high resolution of the newer 5D Mark II, and of course there's no video mode. Comparison tests show much more noise at high ISO levels; in fact, ISO 3200 is the upper limit. However, this camera has established an excellent reputation and would make a fine budget choice.